Blue diamond sells for world record $10.86 mln, Sotheby's says

* Diamond purchased over phone by London luxury jeweller

* Stone likely to be recut, U.S. jeweller says

* About size of almond, gem is "mystical deep blue"

By Stephanie Nebehay

GENEVA, Nov 14 A flawless deep-blue diamond sold
at auction on Wednesday night for 10.27 million Swiss francs
($10.86 million), a world record for a blue diamond per carat
and more than twice its pre-sale estimate, Sotheby's
said.

London luxury jeweller Laurence Graff, bidding by telephone,
bought the drop-shaped stone which weighs 10.48 carats and is
about the size of an almond, it said.

Signed pieces by top designers including Bulgari, Harry
Winston, Van Cleef & Arpels fetched strong prices, easily
exceeding their estimates, at the semi-annual sales in Geneva.

Applause erupted after David Bennett, head of Sotheby's
international jewellery department, brought down the hammer
after heated and lengthy bidding on the blue diamond which had
been estimated to fetch 3.2 million to 4.2 million francs.

"It is certainly a world record price per carat for a deep
blue diamond," Bennett told reporters after the sale. "It is an
extraordinary stone, a very, very mystical deep blue."

"They only come from one mine, the Cullinan mine in South
Africa," he said. The mine is owned by Petra Diamonds.

Mark Emanuel, of American jeweller David Webb, predicted
that the blue diamond, the night's top lot, would be recut.

"It is an extremely rare 10-carat deep blue briolette that
can be recut to a 7-carat vivid blue," Emanuel told Reuters.

"Most of these diamonds are bought on the basis of
speculating and recutting. That's why we come. As a diamond
dealer we look at the potential of a stone," he said.

SPANISH ROYAL BRACELET

A late 1920s Cartier bracelet put up for sale by a member of
the extended Spanish royal family soared to 3 .28 m illion Swiss
francs. Its pre-sale estimate was 750,000-1.3 million.

Sotheby's did not identify the "lady of title" who parted
with the bracelet set with pink conch pearls and diamonds made
in the 1920s for Queen Victoria Eugenia (1887-1969), grandmother
of King Juan Carlos. The buyer was a European private collector.

"It is one of the most charming jewels to come to the
auction block in many years," Bennett said.

"It made a pretty sensational price. This is probably the
most valuable bracelet made by Cartier between the wars."

Only an iconic 1952 Cartier panther bracelet belonging to
the Duchess of Windsor, part of her collection first sold in
1987, is worth more, netting $7 million two years ago, he said.

In all, 521 of 589 lots found new owners for a total of 76.6
million francs, double the low end of the pre-sale estimate.

"Most of the jewels were fresh to the market. Royal
provenance proved to be extremely sought after," Bennett said.

On Tuesday, a huge, internally flawless diamond from India's
fabled Golconda mines sold at auction in Geneva for a record
20.355 million Swiss francs, Christie's said.

The rare, colourless stone weighing 76.02 carats, and
roughly the size of a large strawberry, once belonged to
Archduke Joseph August of Austria (1872-1962), a prince of the
Hungarian line of the Habsburgs.

"At this level of business, the very, very best of coloured
stones and the very, very best of diamonds has almost no limit
in market value," said Emanuel of David Webb.

"People are willing to pay extraordinary prices to have the
very, very best. The extraordinary prices are a sign of surging
demand for the very best from the very wealthy.

"That was true for signed pieces and single stones. In this
market place, quality rules," he said.

Eric Valdieu, an expert formerly with Christie's who has
launched an investment fund called Divine Jewels, said after
attending both sales this week: "This is a sign of a healthy
market, it is weathering the stormy economic climate."

WASHINGTON, Dec 9 Aetna Inc's chief
executive denied on Friday that its withdrawal from some
Obamacare exchanges was in retaliation for government efforts to
halt its merger with Humana Inc, as he sought to
convince a federal judge to approve the deal.

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